Prevalence of prescription drug use among ambulatory adults increases substantially with age. Among people ≥ 65, 90% use at least 1 drug per week, > 40% use at least 5 different drugs per week, and 12% use ≥ 10 different drugs per week. Women take more drugs, particularly psychoactive and arthritis drugs. Drug use is greatest among the frail elderly, hospitalized patients, and nursing home residents; typically, a nursing home resident is given 7 to 8 different drugs on a regular basis.

Providing safe, effective drug therapy for the elderly is challenging for many reasons:

• They use more drugs than any other age group, increasing risk of adverse effects and making adherence difficult.
• They are more likely to have chronic disorders that affect drug response.
• Their physiologic reserves are reduced and can be further reduced by acute and chronic disorders.
• Aging alters pharmacodynamics and pharmacokinetics.
• They may be less able to obtain or afford drugs.

There are 2 main approaches to optimizing drug therapy in the elderly:

• Using appropriate drugs as indicated to maximize effectiveness
• Avoiding adverse drug effects

Because the risk of adverse drug effects is high, overprescribing has been targeted as a major problem in the treatment of the elderly. However, underprescribing appropriate drugs must also be avoided.

Last full review/revision September 2009 by J. Mark Ruscin, PharmD